What is the relative air pressure in the filter area of a CAI?
 

Like the title asks, what is the air pressure in the area right behind the front bumper opening, where a AEM/Mazdaspeed CAI filter sucks in air?

I am pondering how oem placement of a front license plate may affect air induction; would it cause negative pressure or is there a benefit to relocating the plate to the side.
Though this may introduce turbulent air to the filter.

Just some ideas and wondering if anyone has tested this idea.

I don't think it would affect the performance of your intake at all. What I would be more concerned about is how much airflow the licence plate blocks from getting through your radiator; having the plate off to the side would be more beneficial in that aspect. But of course if you mean relocate to a side air dam where it is blocking an oil cooler that is also not beneficial.

I'll go further and say you're wasting your time even thinking about it, let alone starting a thread on the subject. The license plate topic is as old as the forum. Well proven it has no meaningful impact on front bumper flow. Do you realize the top half of the center nose grille is solid i.e. no air flow goes through it?

I am aware of the black grill being solid on the top portion.